Driving mechanism.



PATENTED DEC. 4, 1906.

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E. J. MASON.

DRIVING MECHANISM.

APPLICATION FILED JULY 16, 1908.

WITNESSES. 2d WW UNITED STATES P T NT oEEIoE.

ELLI TT J. MAsoN, OF ALLEGHENY, PENNSYLVANIA, ASSIGNOR To HErL -& PATTERSON INCORPORATED, or PITTSBURG, PENNSYL- mm, A ooRPoRAT1oN OF PENNSYLVANIA.

DRIVING MECHANISM- Specification of Letters Patent.

Application filed July 16, 1906. Serial No. 826,441.

Patented Dec. 4, 1906.

. ism, and. more especially to cases w ere power is to be transmitted from a shaft ca g two ,or' more s rocket wheels driven by chains connecte u to sprocket-Wheels on the power or main S aft. 1 k

A common example of the above is the ordina bucket elevator in which the chains carrying the buckets are driven by sprocket,- wheels rigidly secured to the power-shaft, While the sprocket-wheels at the other points of the elevator, such as in the boot, are usuall arranged so' that one of each such pair sprockets is rigid on the shaft and the other loose.- The loose sprocket takes up an irregularity in the length of the chains. ere 'poweris to be transmitted from the last-named shaft, the chain on the tight sprocket will do all, the work. In order to equalize'the, Wear, however, it has been customary to provide said shaft with keyways, as wel as said sprockets, and then key said sprockets alternately on the shaft, so that one or the other will always be loose to compensate for inequalit in length of chain, and divide the wear on t e chains more equally. The object of my invention is to provide driving mechanismof this character in which provislon is made for the automatic adjustment of the sprockets, so that first one and then the other will be driven by its chain, and so divide the wear and strain between the two chains. To these ends my invention comprises, enerally stated, a power-shaft having s roc ets thereon, chains engaging said sproc ets and driven thereb a secondary power-shaft, sprockets loose y mounted thereon with which said chains engage, and means for automatically throwing said last-named sprockets into 0 efiative engagement with said secondary s a By reference to the drawings, Figure 1 is a side elevation of an elevator with my invention applied thereto. Fig. 2'is an enlarged Fig. 3 is an shaft and the ig. 4 is a cross- Fig. 5 is a pervertical section of the elevator. enlar ed view of the seconda sproc ets carried thereby. section on line 4 4, Fig. 3.

spective of the sleeve.

In the drawings, the numeral 2 designates a suitable bucket elevator with the boot' 3 from which the material is elevated. At the upperend of the elevator is the power-shaft 4, driven by a motor or engine. shaft 4 are the sprocket-Wheels 5, rigidly keyed to said shaft. The chains 6, carrying the buckets 7, pass around the sprocketwheel 5 and around the sprocket-wheel 8, loosely mounted on the secondary shaft 9, journaled in the boot 3. Keyed to the secondary shaft 9 is the sleeve 10, which has an ordinary feather-keywa 11 therein. A pin passes through sai sleeve and shaft to prevent lon 'tudinal movement of said sleeve on said sha t. are, the clutch-jaws 12, which are adapted to enga e the clutch-jaws 13 on'the sprocketwhee s 8. There is a certain amount of play between the jaws of the clutches 12 and-13 On this At the ends of the sleeve 10 1 which ermits the sprockets 8 to move by each 0t er enough to take up any inequalities in the len th of the chains 6, as fully hereinafter set orth. Power ma be transmitted from the shaft 9 to drive the belt conveyor 14. A small sprocket 15 on shaft 9 may be connected up to the sprocket-wheel 16 on the shaft 17 to drive the endless-belt conveyor 14.

When my invention is in use, the power from the shaft 4 drives the chain 6, and the buckets are elevated in the ordinary manner after being filled from the boot 3. In all elevator-chains there is a certain amount of irregularity in the pitch, and although the tota length of two chains will be approximately the same the lengths of any two corres onding intermediate sections will most pro ably be different. The chains also wear unequally when in use. With my invention if one of the chains is longer than the other the shorter chain will naturally do all the work necessary to drive the shaft 9, and accordingly the sprocket at that end of the shaft 9 will be moved to positively engage the clutch of the sleeve 10 and be carried around thereby. If after a time the other chain becomes-the shorter, then the ositions of the sprockets will be reversed an the one at the opposite end of the shaft 9 will become the active one. In this manner automatic-. ally the sprocket-Wheels are positively driven and the wear is divided between the two chains. When the chains wear enough to become of e ual length, then they will both drive. Neit er chain, it is a parent, will be 'used by itself for any great ength of time,

and as a conse uence no unusua wear is put upon any one am.

It is apparent that while Ihave illustrated m invention with the use of two sprockets throwin'gone or the other of said last-named sprocket-wheels into positive, engagement with said secondashaft according as said chains may vary in ength.

2. The combination of a power-shaft, a plurality of s rocket-wheels mounted thereon, a plura 1ty of chains engaging said sprocket-wheels anddriven thereby, a secondary shaft, a plurality of sprocket-wheels loosely mounted thereon around which said chains pass, clutching mechanism on said secondary shaft, and means for automatically throwing one or the other of said lastnamed sprocket-wheels into positive engagement with said secondary shaft according as said chains ma v in length. I

3. The com ination of a power-shaft, a plurality of s rocket-wheels mounted thereon, a plura 1ty of chains engaging said' sprocket-wheels and driven thereby, a sec-' ondary shaft, a plurality of sprocket-wheels .loosely. mounted thereon around which said chains pass, interlocking-clutches on said secondary shaft and on said s rocket-wheels havin a certain amount 0 rotary play, where y one or' the other of said last-named sprocket-wheels will be brought into positive engagement with, said secondary shaft accordin assaidchains ma vary in length.

4. e combination 0 a power-shaft, a

plurality of s rocket-wheels mounted thereon, a plura 1ty of chains engaging saidv sprgicket-wheels and driven thereby, a secon loosely mounted thereon around which said chains pass, a sleeve rigidly mounted on said seconda shaft having interlocking clutches at its en s ada ted to engage corresponding clutches on sai last-named sprocket-wheels with a certain amount of rotary play between said clutches, whereby one or the other of said last named sprocket wheels will be brought into ositive engagement with said secondary sha t according as said chains may vaiy in length.

n testimony whereof I, the said ELLro'rr J. MASON, have hereunto set my hand,

' ELLIOTT J. MASON. Witnesses:

ROBT. D. TOTTEN, J. R. KELLER.

shaft, a plurality of sprocket-wheels 

